| /* |
| * QEMU Block driver for DMG images |
| * |
| * Copyright (c) 2004 Johannes E. Schindelin |
| * |
| * Permission is hereby granted, free of charge, to any person obtaining a copy |
| * of this software and associated documentation files (the "Software"), to deal |
| * in the Software without restriction, including without limitation the rights |
| * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell |
| * copies of the Software, and to permit persons to whom the Software is |
| * furnished to do so, subject to the following conditions: |
| * |
| * The above copyright notice and this permission notice shall be included in |
| * all copies or substantial portions of the Software. |
| * |
| * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL |
| * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, |
| * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN |
| * THE SOFTWARE. |
| */ |
| #include "qemu/osdep.h" |
| #include "qapi/error.h" |
| #include "qemu-common.h" |
| #include "block/block_int.h" |
| #include "qemu/bswap.h" |
| #include "qemu/error-report.h" |
| #include "qemu/module.h" |
| #include <zlib.h> |
| #ifdef CONFIG_BZIP2 |
| #include <bzlib.h> |
| #endif |
| #include <glib.h> |
| |
| enum { |
| /* Limit chunk sizes to prevent unreasonable amounts of memory being used |
| * or truncating when converting to 32-bit types |
| */ |
| DMG_LENGTHS_MAX = 64 * 1024 * 1024, /* 64 MB */ |
| DMG_SECTORCOUNTS_MAX = DMG_LENGTHS_MAX / 512, |
| }; |
| |
| typedef struct BDRVDMGState { |
| CoMutex lock; |
| /* each chunk contains a certain number of sectors, |
| * offsets[i] is the offset in the .dmg file, |
| * lengths[i] is the length of the compressed chunk, |
| * sectors[i] is the sector beginning at offsets[i], |
| * sectorcounts[i] is the number of sectors in that chunk, |
| * the sectors array is ordered |
| * 0<=i<n_chunks */ |
| |
| uint32_t n_chunks; |
| uint32_t* types; |
| uint64_t* offsets; |
| uint64_t* lengths; |
| uint64_t* sectors; |
| uint64_t* sectorcounts; |
| uint32_t current_chunk; |
| uint8_t *compressed_chunk; |
| uint8_t *uncompressed_chunk; |
| z_stream zstream; |
| #ifdef CONFIG_BZIP2 |
| bz_stream bzstream; |
| #endif |
| } BDRVDMGState; |
| |
| static int dmg_probe(const uint8_t *buf, int buf_size, const char *filename) |
| { |
| int len; |
| |
| if (!filename) { |
| return 0; |
| } |
| |
| len = strlen(filename); |
| if (len > 4 && !strcmp(filename + len - 4, ".dmg")) { |
| return 2; |
| } |
| return 0; |
| } |
| |
| static int read_uint64(BlockDriverState *bs, int64_t offset, uint64_t *result) |
| { |
| uint64_t buffer; |
| int ret; |
| |
| ret = bdrv_pread(bs->file->bs, offset, &buffer, 8); |
| if (ret < 0) { |
| return ret; |
| } |
| |
| *result = be64_to_cpu(buffer); |
| return 0; |
| } |
| |
| static int read_uint32(BlockDriverState *bs, int64_t offset, uint32_t *result) |
| { |
| uint32_t buffer; |
| int ret; |
| |
| ret = bdrv_pread(bs->file->bs, offset, &buffer, 4); |
| if (ret < 0) { |
| return ret; |
| } |
| |
| *result = be32_to_cpu(buffer); |
| return 0; |
| } |
| |
| static inline uint64_t buff_read_uint64(const uint8_t *buffer, int64_t offset) |
| { |
| return be64_to_cpu(*(uint64_t *)&buffer[offset]); |
| } |
| |
| static inline uint32_t buff_read_uint32(const uint8_t *buffer, int64_t offset) |
| { |
| return be32_to_cpu(*(uint32_t *)&buffer[offset]); |
| } |
| |
| /* Increase max chunk sizes, if necessary. This function is used to calculate |
| * the buffer sizes needed for compressed/uncompressed chunk I/O. |
| */ |
| static void update_max_chunk_size(BDRVDMGState *s, uint32_t chunk, |
| uint32_t *max_compressed_size, |
| uint32_t *max_sectors_per_chunk) |
| { |
| uint32_t compressed_size = 0; |
| uint32_t uncompressed_sectors = 0; |
| |
| switch (s->types[chunk]) { |
| case 0x80000005: /* zlib compressed */ |
| case 0x80000006: /* bzip2 compressed */ |
| compressed_size = s->lengths[chunk]; |
| uncompressed_sectors = s->sectorcounts[chunk]; |
| break; |
| case 1: /* copy */ |
| uncompressed_sectors = (s->lengths[chunk] + 511) / 512; |
| break; |
| case 2: /* zero */ |
| /* as the all-zeroes block may be large, it is treated specially: the |
| * sector is not copied from a large buffer, a simple memset is used |
| * instead. Therefore uncompressed_sectors does not need to be set. */ |
| break; |
| } |
| |
| if (compressed_size > *max_compressed_size) { |
| *max_compressed_size = compressed_size; |
| } |
| if (uncompressed_sectors > *max_sectors_per_chunk) { |
| *max_sectors_per_chunk = uncompressed_sectors; |
| } |
| } |
| |
| static int64_t dmg_find_koly_offset(BlockDriverState *file_bs, Error **errp) |
| { |
| int64_t length; |
| int64_t offset = 0; |
| uint8_t buffer[515]; |
| int i, ret; |
| |
| /* bdrv_getlength returns a multiple of block size (512), rounded up. Since |
| * dmg images can have odd sizes, try to look for the "koly" magic which |
| * marks the begin of the UDIF trailer (512 bytes). This magic can be found |
| * in the last 511 bytes of the second-last sector or the first 4 bytes of |
| * the last sector (search space: 515 bytes) */ |
| length = bdrv_getlength(file_bs); |
| if (length < 0) { |
| error_setg_errno(errp, -length, |
| "Failed to get file size while reading UDIF trailer"); |
| return length; |
| } else if (length < 512) { |
| error_setg(errp, "dmg file must be at least 512 bytes long"); |
| return -EINVAL; |
| } |
| if (length > 511 + 512) { |
| offset = length - 511 - 512; |
| } |
| length = length < 515 ? length : 515; |
| ret = bdrv_pread(file_bs, offset, buffer, length); |
| if (ret < 0) { |
| error_setg_errno(errp, -ret, "Failed while reading UDIF trailer"); |
| return ret; |
| } |
| for (i = 0; i < length - 3; i++) { |
| if (buffer[i] == 'k' && buffer[i+1] == 'o' && |
| buffer[i+2] == 'l' && buffer[i+3] == 'y') { |
| return offset + i; |
| } |
| } |
| error_setg(errp, "Could not locate UDIF trailer in dmg file"); |
| return -EINVAL; |
| } |
| |
| /* used when building the sector table */ |
| typedef struct DmgHeaderState { |
| /* used internally by dmg_read_mish_block to remember offsets of blocks |
| * across calls */ |
| uint64_t data_fork_offset; |
| /* exported for dmg_open */ |
| uint32_t max_compressed_size; |
| uint32_t max_sectors_per_chunk; |
| } DmgHeaderState; |
| |
| static bool dmg_is_known_block_type(uint32_t entry_type) |
| { |
| switch (entry_type) { |
| case 0x00000001: /* uncompressed */ |
| case 0x00000002: /* zeroes */ |
| case 0x80000005: /* zlib */ |
| #ifdef CONFIG_BZIP2 |
| case 0x80000006: /* bzip2 */ |
| #endif |
| return true; |
| default: |
| return false; |
| } |
| } |
| |
| static int dmg_read_mish_block(BDRVDMGState *s, DmgHeaderState *ds, |
| uint8_t *buffer, uint32_t count) |
| { |
| uint32_t type, i; |
| int ret; |
| size_t new_size; |
| uint32_t chunk_count; |
| int64_t offset = 0; |
| uint64_t data_offset; |
| uint64_t in_offset = ds->data_fork_offset; |
| uint64_t out_offset; |
| |
| type = buff_read_uint32(buffer, offset); |
| /* skip data that is not a valid MISH block (invalid magic or too small) */ |
| if (type != 0x6d697368 || count < 244) { |
| /* assume success for now */ |
| return 0; |
| } |
| |
| /* chunk offsets are relative to this sector number */ |
| out_offset = buff_read_uint64(buffer, offset + 8); |
| |
| /* location in data fork for (compressed) blob (in bytes) */ |
| data_offset = buff_read_uint64(buffer, offset + 0x18); |
| in_offset += data_offset; |
| |
| /* move to begin of chunk entries */ |
| offset += 204; |
| |
| chunk_count = (count - 204) / 40; |
| new_size = sizeof(uint64_t) * (s->n_chunks + chunk_count); |
| s->types = g_realloc(s->types, new_size / 2); |
| s->offsets = g_realloc(s->offsets, new_size); |
| s->lengths = g_realloc(s->lengths, new_size); |
| s->sectors = g_realloc(s->sectors, new_size); |
| s->sectorcounts = g_realloc(s->sectorcounts, new_size); |
| |
| for (i = s->n_chunks; i < s->n_chunks + chunk_count; i++) { |
| s->types[i] = buff_read_uint32(buffer, offset); |
| if (!dmg_is_known_block_type(s->types[i])) { |
| chunk_count--; |
| i--; |
| offset += 40; |
| continue; |
| } |
| |
| /* sector number */ |
| s->sectors[i] = buff_read_uint64(buffer, offset + 8); |
| s->sectors[i] += out_offset; |
| |
| /* sector count */ |
| s->sectorcounts[i] = buff_read_uint64(buffer, offset + 0x10); |
| |
| /* all-zeroes sector (type 2) does not need to be "uncompressed" and can |
| * therefore be unbounded. */ |
| if (s->types[i] != 2 && s->sectorcounts[i] > DMG_SECTORCOUNTS_MAX) { |
| error_report("sector count %" PRIu64 " for chunk %" PRIu32 |
| " is larger than max (%u)", |
| s->sectorcounts[i], i, DMG_SECTORCOUNTS_MAX); |
| ret = -EINVAL; |
| goto fail; |
| } |
| |
| /* offset in (compressed) data fork */ |
| s->offsets[i] = buff_read_uint64(buffer, offset + 0x18); |
| s->offsets[i] += in_offset; |
| |
| /* length in (compressed) data fork */ |
| s->lengths[i] = buff_read_uint64(buffer, offset + 0x20); |
| |
| if (s->lengths[i] > DMG_LENGTHS_MAX) { |
| error_report("length %" PRIu64 " for chunk %" PRIu32 |
| " is larger than max (%u)", |
| s->lengths[i], i, DMG_LENGTHS_MAX); |
| ret = -EINVAL; |
| goto fail; |
| } |
| |
| update_max_chunk_size(s, i, &ds->max_compressed_size, |
| &ds->max_sectors_per_chunk); |
| offset += 40; |
| } |
| s->n_chunks += chunk_count; |
| return 0; |
| |
| fail: |
| return ret; |
| } |
| |
| static int dmg_read_resource_fork(BlockDriverState *bs, DmgHeaderState *ds, |
| uint64_t info_begin, uint64_t info_length) |
| { |
| BDRVDMGState *s = bs->opaque; |
| int ret; |
| uint32_t count, rsrc_data_offset; |
| uint8_t *buffer = NULL; |
| uint64_t info_end; |
| uint64_t offset; |
| |
| /* read offset from begin of resource fork (info_begin) to resource data */ |
| ret = read_uint32(bs, info_begin, &rsrc_data_offset); |
| if (ret < 0) { |
| goto fail; |
| } else if (rsrc_data_offset > info_length) { |
| ret = -EINVAL; |
| goto fail; |
| } |
| |
| /* read length of resource data */ |
| ret = read_uint32(bs, info_begin + 8, &count); |
| if (ret < 0) { |
| goto fail; |
| } else if (count == 0 || rsrc_data_offset + count > info_length) { |
| ret = -EINVAL; |
| goto fail; |
| } |
| |
| /* begin of resource data (consisting of one or more resources) */ |
| offset = info_begin + rsrc_data_offset; |
| |
| /* end of resource data (there is possibly a following resource map |
| * which will be ignored). */ |
| info_end = offset + count; |
| |
| /* read offsets (mish blocks) from one or more resources in resource data */ |
| while (offset < info_end) { |
| /* size of following resource */ |
| ret = read_uint32(bs, offset, &count); |
| if (ret < 0) { |
| goto fail; |
| } else if (count == 0 || count > info_end - offset) { |
| ret = -EINVAL; |
| goto fail; |
| } |
| offset += 4; |
| |
| buffer = g_realloc(buffer, count); |
| ret = bdrv_pread(bs->file->bs, offset, buffer, count); |
| if (ret < 0) { |
| goto fail; |
| } |
| |
| ret = dmg_read_mish_block(s, ds, buffer, count); |
| if (ret < 0) { |
| goto fail; |
| } |
| /* advance offset by size of resource */ |
| offset += count; |
| } |
| ret = 0; |
| |
| fail: |
| g_free(buffer); |
| return ret; |
| } |
| |
| static int dmg_read_plist_xml(BlockDriverState *bs, DmgHeaderState *ds, |
| uint64_t info_begin, uint64_t info_length) |
| { |
| BDRVDMGState *s = bs->opaque; |
| int ret; |
| uint8_t *buffer = NULL; |
| char *data_begin, *data_end; |
| |
| /* Have at least some length to avoid NULL for g_malloc. Attempt to set a |
| * safe upper cap on the data length. A test sample had a XML length of |
| * about 1 MiB. */ |
| if (info_length == 0 || info_length > 16 * 1024 * 1024) { |
| ret = -EINVAL; |
| goto fail; |
| } |
| |
| buffer = g_malloc(info_length + 1); |
| buffer[info_length] = '\0'; |
| ret = bdrv_pread(bs->file->bs, info_begin, buffer, info_length); |
| if (ret != info_length) { |
| ret = -EINVAL; |
| goto fail; |
| } |
| |
| /* look for <data>...</data>. The data is 284 (0x11c) bytes after base64 |
| * decode. The actual data element has 431 (0x1af) bytes which includes tabs |
| * and line feeds. */ |
| data_end = (char *)buffer; |
| while ((data_begin = strstr(data_end, "<data>")) != NULL) { |
| guchar *mish; |
| gsize out_len = 0; |
| |
| data_begin += 6; |
| data_end = strstr(data_begin, "</data>"); |
| /* malformed XML? */ |
| if (data_end == NULL) { |
| ret = -EINVAL; |
| goto fail; |
| } |
| *data_end++ = '\0'; |
| mish = g_base64_decode(data_begin, &out_len); |
| ret = dmg_read_mish_block(s, ds, mish, (uint32_t)out_len); |
| g_free(mish); |
| if (ret < 0) { |
| goto fail; |
| } |
| } |
| ret = 0; |
| |
| fail: |
| g_free(buffer); |
| return ret; |
| } |
| |
| static int dmg_open(BlockDriverState *bs, QDict *options, int flags, |
| Error **errp) |
| { |
| BDRVDMGState *s = bs->opaque; |
| DmgHeaderState ds; |
| uint64_t rsrc_fork_offset, rsrc_fork_length; |
| uint64_t plist_xml_offset, plist_xml_length; |
| int64_t offset; |
| int ret; |
| |
| bs->read_only = 1; |
| bs->request_alignment = BDRV_SECTOR_SIZE; /* No sub-sector I/O supported */ |
| |
| s->n_chunks = 0; |
| s->offsets = s->lengths = s->sectors = s->sectorcounts = NULL; |
| /* used by dmg_read_mish_block to keep track of the current I/O position */ |
| ds.data_fork_offset = 0; |
| ds.max_compressed_size = 1; |
| ds.max_sectors_per_chunk = 1; |
| |
| /* locate the UDIF trailer */ |
| offset = dmg_find_koly_offset(bs->file->bs, errp); |
| if (offset < 0) { |
| ret = offset; |
| goto fail; |
| } |
| |
| /* offset of data fork (DataForkOffset) */ |
| ret = read_uint64(bs, offset + 0x18, &ds.data_fork_offset); |
| if (ret < 0) { |
| goto fail; |
| } else if (ds.data_fork_offset > offset) { |
| ret = -EINVAL; |
| goto fail; |
| } |
| |
| /* offset of resource fork (RsrcForkOffset) */ |
| ret = read_uint64(bs, offset + 0x28, &rsrc_fork_offset); |
| if (ret < 0) { |
| goto fail; |
| } |
| ret = read_uint64(bs, offset + 0x30, &rsrc_fork_length); |
| if (ret < 0) { |
| goto fail; |
| } |
| if (rsrc_fork_offset >= offset || |
| rsrc_fork_length > offset - rsrc_fork_offset) { |
| ret = -EINVAL; |
| goto fail; |
| } |
| /* offset of property list (XMLOffset) */ |
| ret = read_uint64(bs, offset + 0xd8, &plist_xml_offset); |
| if (ret < 0) { |
| goto fail; |
| } |
| ret = read_uint64(bs, offset + 0xe0, &plist_xml_length); |
| if (ret < 0) { |
| goto fail; |
| } |
| if (plist_xml_offset >= offset || |
| plist_xml_length > offset - plist_xml_offset) { |
| ret = -EINVAL; |
| goto fail; |
| } |
| ret = read_uint64(bs, offset + 0x1ec, (uint64_t *)&bs->total_sectors); |
| if (ret < 0) { |
| goto fail; |
| } |
| if (bs->total_sectors < 0) { |
| ret = -EINVAL; |
| goto fail; |
| } |
| if (rsrc_fork_length != 0) { |
| ret = dmg_read_resource_fork(bs, &ds, |
| rsrc_fork_offset, rsrc_fork_length); |
| if (ret < 0) { |
| goto fail; |
| } |
| } else if (plist_xml_length != 0) { |
| ret = dmg_read_plist_xml(bs, &ds, plist_xml_offset, plist_xml_length); |
| if (ret < 0) { |
| goto fail; |
| } |
| } else { |
| ret = -EINVAL; |
| goto fail; |
| } |
| |
| /* initialize zlib engine */ |
| s->compressed_chunk = qemu_try_blockalign(bs->file->bs, |
| ds.max_compressed_size + 1); |
| s->uncompressed_chunk = qemu_try_blockalign(bs->file->bs, |
| 512 * ds.max_sectors_per_chunk); |
| if (s->compressed_chunk == NULL || s->uncompressed_chunk == NULL) { |
| ret = -ENOMEM; |
| goto fail; |
| } |
| |
| if (inflateInit(&s->zstream) != Z_OK) { |
| ret = -EINVAL; |
| goto fail; |
| } |
| |
| s->current_chunk = s->n_chunks; |
| |
| qemu_co_mutex_init(&s->lock); |
| return 0; |
| |
| fail: |
| g_free(s->types); |
| g_free(s->offsets); |
| g_free(s->lengths); |
| g_free(s->sectors); |
| g_free(s->sectorcounts); |
| qemu_vfree(s->compressed_chunk); |
| qemu_vfree(s->uncompressed_chunk); |
| return ret; |
| } |
| |
| static inline int is_sector_in_chunk(BDRVDMGState* s, |
| uint32_t chunk_num, uint64_t sector_num) |
| { |
| if (chunk_num >= s->n_chunks || s->sectors[chunk_num] > sector_num || |
| s->sectors[chunk_num] + s->sectorcounts[chunk_num] <= sector_num) { |
| return 0; |
| } else { |
| return -1; |
| } |
| } |
| |
| static inline uint32_t search_chunk(BDRVDMGState *s, uint64_t sector_num) |
| { |
| /* binary search */ |
| uint32_t chunk1 = 0, chunk2 = s->n_chunks, chunk3; |
| while (chunk1 != chunk2) { |
| chunk3 = (chunk1 + chunk2) / 2; |
| if (s->sectors[chunk3] > sector_num) { |
| chunk2 = chunk3; |
| } else if (s->sectors[chunk3] + s->sectorcounts[chunk3] > sector_num) { |
| return chunk3; |
| } else { |
| chunk1 = chunk3; |
| } |
| } |
| return s->n_chunks; /* error */ |
| } |
| |
| static inline int dmg_read_chunk(BlockDriverState *bs, uint64_t sector_num) |
| { |
| BDRVDMGState *s = bs->opaque; |
| |
| if (!is_sector_in_chunk(s, s->current_chunk, sector_num)) { |
| int ret; |
| uint32_t chunk = search_chunk(s, sector_num); |
| #ifdef CONFIG_BZIP2 |
| uint64_t total_out; |
| #endif |
| |
| if (chunk >= s->n_chunks) { |
| return -1; |
| } |
| |
| s->current_chunk = s->n_chunks; |
| switch (s->types[chunk]) { /* block entry type */ |
| case 0x80000005: { /* zlib compressed */ |
| /* we need to buffer, because only the chunk as whole can be |
| * inflated. */ |
| ret = bdrv_pread(bs->file->bs, s->offsets[chunk], |
| s->compressed_chunk, s->lengths[chunk]); |
| if (ret != s->lengths[chunk]) { |
| return -1; |
| } |
| |
| s->zstream.next_in = s->compressed_chunk; |
| s->zstream.avail_in = s->lengths[chunk]; |
| s->zstream.next_out = s->uncompressed_chunk; |
| s->zstream.avail_out = 512 * s->sectorcounts[chunk]; |
| ret = inflateReset(&s->zstream); |
| if (ret != Z_OK) { |
| return -1; |
| } |
| ret = inflate(&s->zstream, Z_FINISH); |
| if (ret != Z_STREAM_END || |
| s->zstream.total_out != 512 * s->sectorcounts[chunk]) { |
| return -1; |
| } |
| break; } |
| #ifdef CONFIG_BZIP2 |
| case 0x80000006: /* bzip2 compressed */ |
| /* we need to buffer, because only the chunk as whole can be |
| * inflated. */ |
| ret = bdrv_pread(bs->file->bs, s->offsets[chunk], |
| s->compressed_chunk, s->lengths[chunk]); |
| if (ret != s->lengths[chunk]) { |
| return -1; |
| } |
| |
| ret = BZ2_bzDecompressInit(&s->bzstream, 0, 0); |
| if (ret != BZ_OK) { |
| return -1; |
| } |
| s->bzstream.next_in = (char *)s->compressed_chunk; |
| s->bzstream.avail_in = (unsigned int) s->lengths[chunk]; |
| s->bzstream.next_out = (char *)s->uncompressed_chunk; |
| s->bzstream.avail_out = (unsigned int) 512 * s->sectorcounts[chunk]; |
| ret = BZ2_bzDecompress(&s->bzstream); |
| total_out = ((uint64_t)s->bzstream.total_out_hi32 << 32) + |
| s->bzstream.total_out_lo32; |
| BZ2_bzDecompressEnd(&s->bzstream); |
| if (ret != BZ_STREAM_END || |
| total_out != 512 * s->sectorcounts[chunk]) { |
| return -1; |
| } |
| break; |
| #endif /* CONFIG_BZIP2 */ |
| case 1: /* copy */ |
| ret = bdrv_pread(bs->file->bs, s->offsets[chunk], |
| s->uncompressed_chunk, s->lengths[chunk]); |
| if (ret != s->lengths[chunk]) { |
| return -1; |
| } |
| break; |
| case 2: /* zero */ |
| /* see dmg_read, it is treated specially. No buffer needs to be |
| * pre-filled, the zeroes can be set directly. */ |
| break; |
| } |
| s->current_chunk = chunk; |
| } |
| return 0; |
| } |
| |
| static int coroutine_fn |
| dmg_co_preadv(BlockDriverState *bs, uint64_t offset, uint64_t bytes, |
| QEMUIOVector *qiov, int flags) |
| { |
| BDRVDMGState *s = bs->opaque; |
| uint64_t sector_num = offset >> BDRV_SECTOR_BITS; |
| int nb_sectors = bytes >> BDRV_SECTOR_BITS; |
| int ret, i; |
| |
| assert((offset & (BDRV_SECTOR_SIZE - 1)) == 0); |
| assert((bytes & (BDRV_SECTOR_SIZE - 1)) == 0); |
| |
| qemu_co_mutex_lock(&s->lock); |
| |
| for (i = 0; i < nb_sectors; i++) { |
| uint32_t sector_offset_in_chunk; |
| void *data; |
| |
| if (dmg_read_chunk(bs, sector_num + i) != 0) { |
| ret = -EIO; |
| goto fail; |
| } |
| /* Special case: current chunk is all zeroes. Do not perform a memcpy as |
| * s->uncompressed_chunk may be too small to cover the large all-zeroes |
| * section. dmg_read_chunk is called to find s->current_chunk */ |
| if (s->types[s->current_chunk] == 2) { /* all zeroes block entry */ |
| qemu_iovec_memset(qiov, i * 512, 0, 512); |
| continue; |
| } |
| sector_offset_in_chunk = sector_num + i - s->sectors[s->current_chunk]; |
| data = s->uncompressed_chunk + sector_offset_in_chunk * 512; |
| qemu_iovec_from_buf(qiov, i * 512, data, 512); |
| } |
| |
| ret = 0; |
| fail: |
| qemu_co_mutex_unlock(&s->lock); |
| return ret; |
| } |
| |
| static void dmg_close(BlockDriverState *bs) |
| { |
| BDRVDMGState *s = bs->opaque; |
| |
| g_free(s->types); |
| g_free(s->offsets); |
| g_free(s->lengths); |
| g_free(s->sectors); |
| g_free(s->sectorcounts); |
| qemu_vfree(s->compressed_chunk); |
| qemu_vfree(s->uncompressed_chunk); |
| |
| inflateEnd(&s->zstream); |
| } |
| |
| static BlockDriver bdrv_dmg = { |
| .format_name = "dmg", |
| .instance_size = sizeof(BDRVDMGState), |
| .bdrv_probe = dmg_probe, |
| .bdrv_open = dmg_open, |
| .bdrv_co_preadv = dmg_co_preadv, |
| .bdrv_close = dmg_close, |
| }; |
| |
| static void bdrv_dmg_init(void) |
| { |
| bdrv_register(&bdrv_dmg); |
| } |
| |
| block_init(bdrv_dmg_init); |